Engine off time-oil check 94 accord

Son has 94 accord four cylinder VTEC. Was visiting for the holidays.
As he was warming up the car to start back I asked if he had checked
oil. He said, no good idea so we turned off the engine waited about
two minutes and then checked. Showed more than a quart low. He was
alarmed but had just driven over a thousand miles on a high mileage
engine and assumed he had burned some. Put a quart in and checked it
again and it showed within the two dipstick holes about three quarters
of a way to the top hole.

He called me on the road when he had stopped for lunch and said the
dipstick then showed about a quarter inch over the full hole
indicating probably a half quart or so too much. The engine on this
check had been off for about thirty minutes. We assumed full drain
back from the head and any other crevices in the engine.

question:

How long should you wait to get a reasonably accurate reading on a
fully warm engine after turning it off?

Is a half quart too much a problem. Should he drain it back to
protect the seals?

thanks

Frank

 

I assume he was alarmed about the oil consumption rate, but
not the low oil level.

As long as the low oil pressure light didn't come on, the
engine should be fine.

hole

Huh. That surprises me a little, based on everything you say
about warming the car up, etc.

Sounds like about half a quart too much.

I don't wait. I turn it off; within five minutes, I check
the level. The manual says to check "a couple of minutes"
after turning the engine off.

Is your son on the road as we speak?

I think, based on my reading, I'd let the extra half-quart
or so go until after the trip. Then I'd do a proper check
(warm up car with say at least twenty minues of driving;
turn off; check oil level). I'd drain to get it between 1/2
and 3/4 on the dipstick.

Too much oil causes frothing, IIRC, which of course cannot
result in optimal lubrication.

OTOH, if the car is consuming oil, it'll be in spec,
level-wise, by trip's end.

On the third hand, if your son is handy and fastidious about
not risking damage to his car, get some Latex gloves for a
few bucks at a drug store, let the car cool down somewhat,
get underneath and drain out the half-quart or so. It's
gonna be messy. Or stop at a Jiffy Lube or a Wal-Mart car
service center and pay them $10 or so to do it.

 

Not enough to worry about. I wouldn't do anything. How long since the last
oil change? When the level suddenly goes up like that, the first suspect is
that the oil filter is full & has gone into bypass mode.

 

eh? the oil filer is full as soon as the pump starts working - assuming
there's enough oil to reach the scavenger pipe and fill the pump.

 

that's very bad practice btw. start it and start driving right away
[but NO full throttle until warm]. idling to warm it exposes the motor
to massively prolonged rich mixture which dilutes the oil film on the
cylinder walls, contaminates the oil, leads to excess carbon build-up,
etc. the old days of high oil viscosity at low temps are OVER. start
and drive.

5-10 mins.

 

He started the engine cold which pumped the thick cold oil up in the engine.
It could take hours or even days to drain back down when cold. That is the
reason it showed so low after only two minutes. You should have brought it
up close to the bottom hole and run the engine until hot. Let it drain for
10 or 15 minutes and then check the level. Oil expands some when hot. Being
a half quart high won't hurt. If it had been a problem he would have seen
foaming on the dipstick because when too high the crank and connecting rods
hit the oil and whip it like a beaten egg. Explain to your son that the oil
should be checked at the least whenever he fuels the car. He should also
check all other fluids at the same time. If he doesn't drive much he should
check them weekly.

 

Oil was changed just before he came to my house. Trip is just over a
thousand miles, so filter was relatively new. Oil looked clean.

 

I'm also assuming the car was on perfectly flat ground both times while
checking? I've found it can vary a little based on where the car is parked
when checking, ie on a slight incline in a driveway.

-Dave

 

Reading the section on "Checking the oil in your engine, and topping up"
from this web page http://www.carbibles.com/engineoil_bible.html should
solve your mystery.

 

couple minutes should do it

nope. perhaps it wasnt checked on level ground? either at your home or
on the road? if the nose (front) is pointing down a slight bit, the oil
will tend to read high. i think.

 

Safest and most accurate time to check: Cold. After sitting overnight.

The car must be sitting in the same attitude (angle of tilt) for each
check.

Oil expands with heat. And it will drain back at a different rate depending
on how hot it is. A winter's drive of fifteen minutes may only heat the oil
up to 120º. An hour's drive may see it go up to 210º. This will make a
difference in the expansion rate and thus the report the stick gives.

Also: if the oil has lots of water and fuel in it when you check, and you
then drive a long distance, that contamination will burn off, giving a low
reading the next time the oil is checked.

Nope. Just leave it. If there's really that much in there, that is, that
is.

 

were you on a hill when you checked it? i just dont see how letting it
cool could change it so much since at oil change shops and what not
they check it right when u pull in, how hot your engine is shouldnt
effect your oil level, you were prob just sittin on a small hill when u
checked it the first time, then when he stoped he was on level or a
hill goin the other way.